Referring to FIG. 1, a prior art tooth mold retaining frame 90 is illustrated. A seat 91 is pivoted with an upper seat 92 at an upper end thereof. A lower end of the seat has a lower seat 93. The upper seat 92 has a positioning block 921 and the lower seat 93 has a positioning block 931. The positioning blocks 921, 931 have respective magnets. A shaped teeth mold T is absorbed between the upper seat and the lower seat. The upper seat 92 is pivotally rotated with respect to the seat 91 so as to view the engagement of the teeth of the teeth mold T. Moreover, a front end and a rear end of the upper seat 92 are installed with fine-adjust devices 94, 95 for controlling the height or opening of the teeth mold T so as to adjust the position of the teeth mold T so that the worker can adjust the engagement of the teeth.
Referring to FIG. 1A, in use of the tooth mold retaining frame 90, some limitation are required. For example, when an iron sheet B is placed on the magnet of the set, in current technology, in the initial stage, a rubber ring encloses the upper seat 92 or the lower seat 93. The gypsum is filled into a mold A as a teeth mold seat T1. Then a prepared teeth mold is placed thereon. After drying, the mold A is taken down so as to complete the teeth mold T. Then another symmetrical engaged teeth mold T2 is made and then complete the respective symmetrical teeth mold T′. However the teeth molds T and T′ will have different compression ratios due to different solidifying states so that errors in biting are induced. The precision in the manufactured denture is not good. Each tooth mold retaining frame has errors in the manufacturing process. The teeth molds T and T′ made by the same tooth mold retaining frame can not be used with another tooth mold retaining frame 90. Thus, the teeth molds T and T′ and the tooth mold retaining frame must be sent to the dentist together for aligning in the engagement and communicates with the patient. However the tooth mold retaining frame can not be used to make another teeth mold during this time period.